Forward-fired automatic tissue sampling apparatus with safety lock

ABSTRACT

An apparatus for the automated and facilitated handling and operation of a biopsy needle system, having a first needle component and a second needle component. The first and second needles are provided with first and second handles, respectively, which are fitted into first and second yokes of the apparatus. The apparatus is configured to maintain the first and second needles in a first position, during insertion of the biopsy needle point into the tissue being sampled. The apparatus is further configured to forwardly move the first and second needles into subsequent positions, respectively, in rapid, automated succession so as to segment and enclose a tissue sample, which may be tested after removal of the biopsy needle system from the tissue. A tissue sample inspection feature permits facilitated repositioning and maintenance of the first needle relative to the second needle after retrieval of the tissue sample to, in turn, enable inspection of the retrieved tissue sample without removal of either needle from the apparatus. The apparatus is further configured so as to be actuatable from positions adjacent the front or the rear of the apparatus housing. A safety lock feature is provided, which prevents inadvertent cocking motions, when the apparatus is actuated by either its rear or forward firing buttons.

BACKGROUND OF THE INVENTION

1. The Technical Field

The present invention relates to tissue sampling devices associated withbiopsy needles, and in particular, to an automatic tissue samplingapparatus for utilizing two-piece biopsy needle systems for facilitatingthe retrieval of a tissue sample for testing.

2. The Prior Art

A typical biopsy needle system utilized in obtaining tissue samples iscomposed of two parts, a first needle and a second needle. The firstneedle consists of a substantially solid shaft, having a first handledisposed at one end. A cutting point, to facilitate insertion of theneedle into the tissue to be sampled, is located at the other end of theshaft, opposite to the position of the handle. Positioned proximate tothe cutting point is a tissue holding region, which is in the form of acut-out region or flat in the otherwise substantially cylindrical shaft.

The second needle is typically hollow, and has a cutting point disposedat one end. At the other end, a second handle is disposed. The hollowpassageway extends through the second handle, to enable the solid shaftof the first needle to be inserted into the passageway and into andthrough the entire hollow shaft of the second needle.

The shaft of the first, inner, solid needle is typically greater inlength than the entire second, outer, hollow needle structure. When thefirst and second handles are placed in a particularly spaced co-axialconfiguration, the hollow shaft of the second needle covers the tissueholding region of the first needle. The tissue holding region may beexposed by projecting the first needle further into the second needle,bringing the first and second handles closer together.

To obtain a tissue sample, the biopsy needle system is typicallyinserted into a patient, into the specific tissue to be sampled, at thedesired cell mass to be investigated, with the first and second needlesrelatively positioned in the first described configuration, so that thetissue holding region is covered. The tissue holding region is thenexposed, by the operator holding the second handle of the second needlestable while projecting the first needle forward a short distance alongits sharp pointed region-until a portion of the tissue being testedsurrounds the flat cut-out of the tissue holding region.

The second needle, which also has a sharp, though hollow, point disposedat the end of the hollow shaft opposite the second handle, is then movedforward, relative to the now-stabilized first needle—to cut off thetissue sample from the rest of the tissue, and cover the tissue sampleabout the flat cut-out of the tissue holding region. The angled cuttingpoint of the second needle serves to sever the tissue sample. The firstand second needles are typically maintained in a particular angularconcentric orientation with respect to one another, prior to insertion,so as to maintain the forwardmost portion of the second needle pointcentered when positioned over the flat, cut-out region of the firstneedle.

After the tissue is severed and confined between the first and secondneedles, the first and second needles will be brought back to the samerelative positions they occupied immediately prior to initial insertionof the biopsy needle system into the patient. To prevent loss orcontamination of the tissue sample, the first and second needles aretypically removed from the patient in this tissue-isolatingconfiguration.

As the configuration of the first and second needles, utilized forinitial insertion, and final removal from the patient, requires that thefirst and second handles be spaced apart in a particular configuration,the manual manipulation of such a biopsy needle system requiresconsiderable dexterity, concentration and skill on the part of theoperator. The concentration necessary to maintain the proper spacing maydetract from the concentration necessary to make insertion and removalof the biopsy needle as painless as possible for the patient.Accordingly, it is desirable to provide a form of automatic tissuesampling apparatus, which accomplishes some, if not all of the handlingsteps just described—so that the operator may be concerned with thecrucial initial step of insertion and final step of removal, of thebiopsy needle system; to reduce the amount of discomfort to the patient,to improve the quality of the results of the tissue sampling procedure,and to enhance the successful repeatability of the procedure, from onepatient to the next.

Examples of prior art automatic tissue sampling apparatus include thosedisclosed in PCT application No. PCT/SE83/00112, Swedish Patent No.8600755, U.S. Pat. No. 4,699,154, issued to Lindgren, U.S. Pat. Nos.4,944,308, and 4,953,558, issued to Akerfeldt, EPO Application No. 0 318447 and Swiss Patent No. 483 829.

In the PCT '00112 application, an automatic tissue sampling apparatus isdisclosed, in which the first needle of the biopsy needle system ispropelled forward by a pressure plate which is driven by a compressedspring, and the second needle is propelled by a movable slide whichreceives the second handle of the second needle. The movable slide forholding the second needle is also propelled by a compressed spring. Inorder to prepare the apparatus for use, each of the springs andrespective slides must be cocked separately, either manually or throughthe use of a specially shaped tool. The slide for the second handle isheld in place by a catch which is configured to be released upon contactwith a projection arranged upon the slide for the first handle of thefirst needle. The pressure plate for the first handle of the firstneedle is, in turn, retained in its cocked position by a trigger whichis actuatable by the operator. While it is possible to cock each of thespring with the biopsy needle already in place, it is contemplated thatsuch cocking could take place well prior to loading of the needle.

In the operation of the PCT '00112 device, once the springs have beencocked and the biopsy needle system has been loaded (either before orafter cocking), the operator inserts the biopsy needle system into thetissue to be sampled, as previously described. He or she may thendepress the trigger which releases the spring for propelling the firstneedle. As the first needle is moved forward, the pressure platereleases the retaining mechanism which has been previously holding themovable slide for the second handle of the second needle. The secondneedle is thus moved forward shortly after the first needle, completingthe sampling movement. The trigger in the apparatus is biased by aspring into position to retain the compressed spring for the firstneedle slide, and is configured to provide increasing resistance todepression, up until a predetermined position, at which point, theresistance is sharply increased and further depression results in theimmediate release of the compressed spring. No means are provided forpreventing inadvertent actuation of the automatic tissue samplingapparatus.

Due to the inherently hazardous nature of the extremely sharp points ofthe biopsy needle and the power of the spring-loaded mechanism, it isdesirable, therefore, to provide a tissue sampling apparatus which hasan automatically engaging safety mechanism, which must be consciouslyovercome before the tissue sampling apparatus may be actuated. Inaddition, it may be often awkward and/or difficult to manually overcomethe force of the uncompressed springs which drive the movable slides.Accordingly, it would be desirable to provide an automatic tissuesampling apparatus which may be readily prepared for use, immediatelybefore insertion, without the need for extreme physical exertion or theuse of awkward and/or specially configured tools.

The tissue sampling device embodied in U.S. Pat. No. 4,699,154 toLindgren discloses a housing in which two slides are mounted forlongitudinal movement, the slides being configured to receive the firstand second handles of the first and second needles, respectively. Eachof the slides is propelled by a pair of compressed springs. The rearwardslide, for propelling the handle of the first needle, is propelled bysprings which bear against a rear wall of the housing. The slide for thehandle of the second needle is propelled by compressed springs whichbear against a fixed, transversely-extending wall arranged in thehousing between the forward and rear slides. Both of the slides arearranged to have a guide member extending through them. A drawbolt isoperably associated with each of the slides for limited axial movementrelative thereto such that when the drawbolt is pulled backward, both ofthe slides are simultaneously drawn against the bias of the respectivesprings, to a cocking position. When the cocking position is reached,retaining members associated with each of the slides engage therespective slides to retain them in their cocked positions.

In a manner similar to that discussed with regard to the PCT '00112application, an external triggering mechanism is provided, which isactuatable by the operator to release the retaining mechanism for theslide for the first needle. Once the slide for the first needle has beenpropelled forward a predetermined distance, a projection on the firstslide releases the retaining mechanism for the slide for the handle ofthe second needle, enabling it to be propelled forward by its respectivesprings.

One possible drawback to the tissue sampling apparatus of the Lindgren'154 patent is that it is configured so that both sets of springs arecompressed, and the slides brought into their retained positions by asingle pulling motion upon the drawbolt. Accordingly, the combinedstrengths of all of the springs must be overcome in order to cock themechanism. Due to the substantial power stored in the springs which isnecessary for the rapid operation of the tissue sampling apparatus, itmay be difficult for certain operators to rapidly and easily operate thecocking mechanism. Accordingly, the prior art addressed an automatictissue sampling apparatus with a built-in cocking mechanism which isreadily and easily operated, and which does not require substantialstrength or effort in order to arm the apparatus. See, e.g., Schramm,U.S. Pat. No. 5,507,298.

The tissue sampling device of the Lindgren '154 patent is also providedwith a safety mechanism, for precluding inadvertent actuation. However,the safety mechanism is configured such that it must be positivelyengaged by the operator, in order to place the tissue sampling apparatusinto condition that it cannot be accidentally fired. Accordingly, theeffectiveness of the safety device is dependent upon the operatorremembering to set the safety. It would be more desirable to provide anautomatic tissue sampling apparatus which is configured with a safetydevice which engages automatically upon the cocking of the apparatus,and is thereby not dependent upon the operator's remembering to engagethe safety. Rather, it would be desirable to configure the safety deviceso the operator must affirmatively disengage the safety before thetissue sampling apparatus can be actuated to fire it.

Swiss Patent No. 483 829 discloses a “gun”-shaped automatic tissuesampling apparatus, in which the springs are cocked by direct pullingforce, and so suffers from the same potential drawback of requiringsubstantial difficulty and effort to arm the device.

U.S. Pats. Nos. 4,944,308 and 4,953,558, issued to Akerfeldt, and EPOApplication No. 0 318 447 disclose an automatic tissue samplingapparatus, in which the springs for the slides for the first and secondneedles are cocked by rotating in a sequential manner. Tabs on theslides ride on cam surfaces to force the slides backward against thesprings requiring substantial effort to operate.

In addition to the foregoing, it is well known that often during tissuesampling procedures, the quality and/or quantity of the tissue beingsampled may vary from procedure to procedure.

Accordingly, it has been desirable to provide a means for permittinginspection of the tissue sample, without removing the biopsy needlecomponents from the tissue sampling apparatus. In that way, should thesize or quality of the sample be inadequate, the biopsy needle may bereinserted into the very same patient for another attempt at obtaining asuitable sample. Such a sample inspection procedure has also permittedaccess to the sample for subsequent deposit of same onto a microscopeslide or other sample holding apparatus for further processing of thetissue sample.

Such prior art tissue sampling apparatus such as those disclosed in thePCT '00112 application and in the Lindgren '154 patent are known to belarge, relatively heavy and complicated devices, which are alsorelatively costly.

The prior art endeavored to provide an improved automatic tissuesampling apparatus which is easy to load and bring into readiness foruse, without undue exertion and/or complicated manipulation of itscomponents; while providing a facilitated, positive locking, tissuesample inspection capability.

Thus, the prior art has provided an automatic tissue sampling apparatuswhich is provided with an automatically engaging safety device, whichdoes not rely upon the operator for its effectiveness and which must beaffirmatively disengaged before the tissue sampling apparatus may beactuated.

The prior art also sought, as another goal, the provision of anautomatic tissue sampling apparatus which is less complicated andtherefore easier and less expensive to construct, and which has alighter construction for greater ease of operation and manipulation.

Yet another goal of the prior art was to provide an automatic tissuesampling apparatus which is provided with various internal shock andsound absorbing means so as to render the apparatus quieter and lessjarring in operation, so as to decrease the actual and/or perceiveddiscomfort of the patient during the tissue sampling procedure, whileensuring better practitioner accuracy during the procedure.

In the prior art apparatus of U.S. patent application Ser. No.07/753,602, now U.S. Pat. No. 5,284,156, the handles of the first andsecond needles were borne upon separate yokes which were each configuredfor longitudinal reciprocating movement within a housing. Both yokeswere biased toward the front of the housing and, when the device iscocked, were held in retracted positions by separate retainingmechanism. When the apparatus was “fired”, the yoke bearing the handleof the first needle moved rapidly forward, and as it approached itsforwardmost position, it approached a central support. Resilient memberson the yoke and on the central support member caused the yoke todecelerate prior to its contact with the central support. Before theresilient members could cause the yoke to “rebound” from the centralsupport, a second “firing” button on the yoke released the retainingmechanism holding the yoke for the second needle. The resilient membersby then exerted sufficient force to slightly force the first yokebackward a short distance from the central support. This rebound wasnecessary to permit the retaining mechanism for the second yoke toengage during subsequent cocking of the apparatus.

While the structure and mode of operation of the prior art automatictissue sampling apparatus of application Ser. No. 07/753,602, U.S. Pat.No. 5,284,156, represented a substantial improvement over the prior artin terms of shock and noise reduction, as well as with respect to easeand safety of operation, some jarring could still exist during operationand, as a general matter, it is always desirable to seek to improve onthe performance of such a device, to reduce such jarring to both improvea patient's physical and psychological well-being, and as well tofurther improve upon the effectiveness of the device in retrievingtissue samples.

Tissue sampling apparatus which have rearwardly positioned actuationbuttons may require that the operator reposition his/her grip, since itis often the situation that the apparatus is grasped at a forward endduring placement of the needle in the patient. To address this, theprior art sought to provide an automatic tissue sampling apparatus whichhas a firing member which is accessible without requiring repositioningof the operator's grip prior to actuation of the apparatus.

An automatic tissue sampling apparatus having a forward locatedactuating button is disclosed in prior art reference Schramm et al.,U.S. Pat. No. 5,507,298. While the apparatus disclosed in that referencelikewise represented a significant advance in the art of automatictissue sampling apparatuses, that device is not without certainfunctional features which may be of concern. Specifically, the safetymechanism provided in that apparatus, for preventing undesired actuationof the apparatus, comprises, in part, a laterally slidable (dependingupon the “cocked” status of the device) shaft. As the device is cocked,the shaft is moved laterally, by following a cam surface on the cockingshaft, to a position which prevents the front and rear firing buttons(which are mechanically interlocked) from being actuated, until suchtime as the shaft is moved back to its original position. However, ithas been found that in the process of exerting pressure on the rearfiring button to actuate the automatic tissue sampling apparatus, inthis type of device, a user can sometimes inadvertently exert upwardforce on the cocking lever, causing it to be moved away from its “atrest” position, while the firing action is taking place. When thecocking shaft is away from its “at rest” positions, during the firingaction, it is possible for some of the internal components to clash,resulting in component stresses, including possible damage to thestructure.

Therefore, it is an additional object of the invention to provide animproved automatic tissue sampling apparatus which is provided with animproved safety lock structure, which is configured to preventinadvertent cocking movements of the cocking mechanism, so as topreclude disruption of the firing action as well as to reduce theundesired stresses and interferences amongst the structural components,toward improved apparatus operation, including sampling reliability andreduced potential for internal damage to the apparatus, during firing.

These and other objects and goals of the invention will become apparentin light of the present Specification, Drawings and Claims.

SUMMARY OF THE INVENTION

The present invention comprises an automatic tissue sampling apparatus,for use with a biopsy needle system of the kind including a first needlehaving a shaft member and two ends, a first handle disposed at one endof the shaft member, a cutting point disposed at the other end of theshaft member, and a tissue holding region positioned between the cuttingpoint and the first handle, and a second needle having a hollow shaft, acutting point disposed at one end of the hollow shaft, and a secondhandle with a passageway arranged therethrough for reciprocation of thefirst needle.

The automatic tissue sampling apparatus comprises a housing. Handleholders are operably disposed in the housing, for receiving and holdingthe first and second handles of the first and second needles, towardmoving same. A propulsion mechanism is operably disposed in the housing,for moving the handle holders within the housing, so as to move theneedle handles to expose and subsequently cover, the tissue holdingregion, when the biopsy needle system has been positioned at a desiredlocation within a tissue to be sampled, the propulsion mechanism beingoperably biased so as to tend to move the handle holders so as to exposeand subsequently cover the tissue holding region, unless the handleholders are restrained. A cocking mechanism is provided, for placing thehandle holders, and, in turn, the first and second needles of the biopsyneedle system into suitable respective positions within the housing forsubsequent movement by the propulsion mechanism. A retaining mechanismis provided for holding the handle holders, and, in turn, the first andsecond needles of the biopsy needle system in the suitable respectivepositions within the housing, prior to actuation of the apparatus. Arelease mechanism is provided for actuating the retaining mechanism, soas to release the handle holders and enable the propulsion mechanism tomove the first and second needles, so as to expose, and subsequentlycover the tissue holding region. A firing mechanism is provided which isoperably connected to the release mechanism, for causing the actuationof the propulsion mechanism. A safety lock mechanism is operablyinterconnected between the firing mechanism and the cocking mechanism,for precluding undesired actuation of the firing mechanism until bothhandle holders are fully cocked, and for precluding undesired actuationof the cocking mechanism, during actuation of the firing mechanism.

The cocking mechanism preferably comprises a cocking shaft, mounted inthe housing for longitudinal reciprocating movement therein, andoperably interconnected with the handle holders; and a cocking leverpivotably mounted on a rear wall portion of the housing, proximate therear firing member, and connected to the cocking shaft so that uponupward pivoting of the cocking lever, the cocking shaft is drawnrearwardly relative to the housing.

Preferably, the safety lock mechanism comprises a safety button, mountedin the rear portion of the housing, for reciprocating movement in adirection transverse to the cocking shaft between first and secondpositions. The safety button has engagement structures disposed thereon,configured for selective engagement with the cocking shaft, when thesafety button is in its first position, and with the rear firing member,when the safety button is in its second position, so that when thesafety button is in its first position, the cocking shaft and, in turn,the cocking lever, are precluded from movement, and when the safetybutton is in its second position, the firing button is precluded frommovement. Simply put, when the safety button is in its first position,one can operate the rear firing member but cannot operate the cockinglever. Alternatively, when the safety button is in its second position,one can operate the cocking lever, but cannot depress the rear firingmember.

In this embodiment, the safety button has a first notch, with anengagement shoulder therein, operably configured to enable the cockingshaft to move relative to the safety button when the safety button is inits second position, and to engage with a shoulder disposed on thecocking shaft to prevent movement of the cocking shaft relative to thesafety button, when the safety button is in its first position. Thesafety button preferably has a second notch, operably configured toenable the rear firing button to move, when the safety button is in itsfirst position, and to engage with a shoulder disposed on the rearfiring button, to preclude movement thereof, when the safety button isin its second position.

In a preferred embodiment, the firing mechanism comprises a rear firingmember operably positioned on a rearward portion of the housing. Theautomatic tissue sampling apparatus preferably further comprises a frontfiring member operably positioned on a forward portion of the housing,the front firing member being operably interconnected with the rearfiring member.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a prior art automatic tissue samplingapparatus, having a double-needle biopsy needle system loaded therein.

FIG. 2 is a perspective view of the apparatus according to FIG. 1, withthe cover opened to show how the biopsy needle system is loaded into theapparatus.

FIG. 3 is a perspective view of the apparatus, according to FIG. 2,showing, in partial cutaway, further details of the construction of theapparatus.

FIG. 4 is a top plan view of the apparatus, according to FIG. 2.

FIG. 5 is a side elevation, in section, of the prior art apparatus, witha biopsy needle system loaded therein, in its initial configurationprior to cocking, further showing, in enlargement, the relativepositions of the needles.

FIG. 6 is a side elevation, in section, showing the apparatus accordingto FIG. 5 during the first cocking stroke, further showing, inenlargement, the relative positions of the handles.

FIG. 7 is a side elevation, in section, of the apparatus according toFIG. 5, showing the apparatus upon completion of the first cockingstroke and release of the cocking elements immediately thereafter,further showing, in enlargement, the relative positions of the needles.

FIG. 8 is a side elevation, in section, of the apparatus according toFIG. 5, shown during the second cocking stroke further showing, inenlargement, the relative positions of the needles.

FIG. 9 is a side elevation, in section, of the apparatus according toFIG. 5, shown fully cocked, after release of the cocking elements, andready for insertion of the biopsy needle system into the tissue to besampled, further showing, in enlargement, the relative positions of theneedles.

FIG. 10 is a side elevation, in section, of the apparatus according toFIG. 5, shown immediately after the button has been depressed, furthershowing, in enlargement, the relative positions of the needles.

FIG. 11 is a side elevation of the apparatus, in section, according toFIG. 5, showing the apparatus after firing but before the yokes havereturned to their initial positions, equivalent to the positions priorto cocking, further showing, in enlargement, the relative positions ofthe needles.

FIG. 12 is a schematic perspective view, illustrating the operation ofthe automatically deployed safety mechanism.

FIG. 13 is a top perspective view, in partial section, of another priorart automatic tissue sampling apparatus, in which at least a frontfiring member is positioned for actuation of the apparatus.

FIG. 14 is a side elevation, in partial section, of an alternativepreferred embodiment of the device of FIG. 13.

FIG. 15 is a front elevation of the apparatus shown in FIG. 13.

FIG. 16 is a side elevation of an automatic tissue sampling apparatus,according to a preferred embodiment of the present invention.

FIG. 17 is a top plan view of the automatic tissue sampling apparatus ofFIG. 16, with the cover opened to illustrate the interior mechanism ofthe automatic tissue sampling apparatus, in the uncocked/firedconfiguration.

FIG. 18 is a side elevation, in section, of the automatic tissuesampling apparatus, according to the embodiment of FIGS. 16-17, takenalong line A-A of FIG. 23, showing the interior mechanism in theuncocked/fired configuration.

FIG. 19. is a side elevation, in section, of the automatic tissuesampling apparatus according to the embodiment of FIGS. 16-18, takenalong line A-A of FIG. 23, showing the interior mechanism in thehalf-cocked/sample notch exposed position.

FIG. 20 is an end elevation, in section, of the automatic tissuesampling apparatus according to the embodiment of FIGS. 16-19, takenalong line B-B of FIG. 18.

FIG. 21 is an end elevation, in section, of the automatic tissuesampling apparatus according to the embodiment of FIGS. 16-20, takenalong line C-C of FIG. 18.

FIG. 22 is a front end elevation of the automatic tissue samplingapparatus according to the embodiment of FIGS. 16-21.

FIG. 23 is a rear end elevation of the automatic tissue samplingapparatus according to the embodiment of FIGS. 16-22.

FIG. 24 is a fragmentary side section of the automatic tissue samplingapparatus according to the embodiment of FIGS. 16-23, taken along lineH-H of FIG. 17.

FIG. 25 is a fragmentary side section of the automatic tissue samplingapparatus according to the embodiment of FIGS. 16-24, taken along lineE-E of FIG. 17.

FIG. 26 is a fragmentary top section of the safety lock portion of theautomatic tissue sampling apparatus according to the embodiment of FIGS.16-25, taken along line D-D of FIG. 16.

FIG. 27 is a fragmentary side section of the automatic tissue samplingapparatus according to the embodiment of FIGS. 16-26, taken along lineF-F of FIG. 17.

FIG. 28 is an end elevation in section of the automatic tissue samplingapparatus according to the embodiment of FIGS. 16-27, taken along lineG-G of FIG. 18.

FIG. 29 is an end elevation in section of the automatic tissue samplingapparatus according to the embodiment of FIGS. 16-28, taken along lineI-I of FIG. 18.

FIG. 30 is a top plan view of the cocking shaft for the automatic tissuesampling apparatus according to the embodiment of FIGS. 16-29.

FIG. 31 is a side elevation of the cocking shaft for the automatictissue sampling apparatus according to the embodiment of FIGS. 16-30.

FIG. 32 is an end elevation, in section, taken along line D-D of FIG.30.

FIG. 33 is an end elevation, in section, taken along line C-C of FIG.32.

FIG. 34 is a perspective view of portions of the safety lock mechanismof the embodiment of FIGS. 16-34.

FIG. 35 is a perspective view of a needle system for use with theautomatic tissue sampling apparatus of FIGS. 16-34.

DETAILED DESCRIPTION OF THE DRAWINGS

While the present invention is susceptible of embodiment in manydifferent forms, there is shown in the drawings and will be describedherein in detail, several specific embodiments, with the understandingthat the present disclosure is to be considered as an exemplification ofthe principles of the invention, and is not intended to limit theinvention to the embodiments illustrated.

A prior art automatic tissue sampling apparatus 20 is illustrated inFIGS. 1-12, having biopsy needle system 22 already loaded therein.Automatic tissue sampling apparatus 20 includes housing 24 with cover25. Automatic tissue sampling apparatus 20 is cocked using lever 28,which is provided with finger gripping portion 29 and thumb rest portion30. Lever 28 is mounted for facilitated pivotal movement around pin 32,which is mounted in projection 33 of housing 24. Upon cocking, safetybutton 35 automatically shifts to one side and prevents button 36 frombeing inadvertently pressed. In order to enable button 36 to bedepressed, safety button 35 must be pushed back in the oppositedirection.

FIG. 2 illustrates cover 25, which may be hinged to housing 24 so as toopen in the manner shown. Spring catch 37 (shown in FIG. 3) holds cover25 in the closed position, but upon moderate upward pressure to cover25, will deflect sufficiently to release cover 25. Central support 39 isfixably mounted generally along the longitudinal center of housing 24,and generally divides the interior of housing 24 into a forward regionand a rearward region. Shaft 40 is arranged for reciprocating axialmovement substantially parallel to the longitudinal axis of housing 24,and is mechanically connected to lever 28 by crank 42, which is, inturn, pivotably connected to lever 28 by pin 43 and pivotably connectedto shaft 40 by pin 44. Accordingly, when lever 28 is pivoted in thedirection indicated by arrow A, shaft 40 moves axially backward withrespect to housing 24. Yokes 46 and 47 are each configured to beretained within housing 24 by projecting tabs, such as tab 49 of yoke46, which are received within longitudinally extending grooves, such asgroove 50. Accordingly, yokes 46 and 47 are each configured to belongitudinally, slidably moved relative to support housing 24.

Shaft 40 is configured to pass through yokes 46 and 47, throughapertures 23 and 53, respectively. Yokes 46 and 47 are each biasedforwardly, with respect to housing 24, by coil springs 55 and 56,respectively. When yoke 46 is drawn toward rear wall 26 of housing 24during cocking (as described hereinafter), it is engaged and retainedadjacent rear wall 26 by retaining member 58. Retaining member 58 isnormally biased to pivot in a clockwise direction around axis 59 so thatengagement portions 60 of retaining member 58 are normally biased tomove upwardly relative to housing 24. Engagement portions 60, which arewedge-shaped, are driven downwardly by pins 61 (as shown in FIG. 3),until pins 61 pass the rear edges of engagement portions 60, as yoke 46approaches rear wall 26. Once pins 61 have passed the rear edges ofengagement portions 60, retaining member 58 is permitted to then rotateclockwise and pins 61 abut the rear edges of engagement portions 60,preventing yoke 46 from being driven forward under the bias ofnow-compressed spring 55.

FIG. 3 illustrates automatic tissue sampling apparatus 20 with yokes 46and 47 in their fully cocked positions. Spring 62, which is weaker thaneither of springs 55 or 56, at one end abuts yoke 47 and at the otherend abuts cross member 64. Spring 62, being at all times in a slightlycompressed configuration, tends to push cross member 64 and yoke 47apart, thereby tending to maintain shaft 40 in a forwardly drawnposition with respect to, and substantially fully within, housing 24.Shaft 40 is provided with a longitudinally extending recess 65 withsharply defined end surfaces 66 and 67 as shown in FIGS. 5-11.

Yoke 47 is illustrated, in FIG. 3, in its retained position againstcentral support 39. To draw yoke 47 against central support 39, againstthe bias of spring 56, when lever 28 is actuated, cross member 64 abutsthe front edge of yoke 47 and forces yoke 47 backward toward centralsupport 39. Yoke 47 is restrained in that position by retaining member70, which is arranged for pivotal movement about axis 71. Retainingmember 70 includes engagement portions 72, which engage pin 73 (see, forexample, FIG. 5) in substantially the same manner as engagement portions60 of retaining member 58 engage pins 61 of yoke 46. Retaining member 70is, like retaining member 58, biased to pivot toward the clockwisedirection (as seen in FIG. 3) and engagement portions 72 arewedge-shaped so that as yoke 47 approaches central support 39, pins 73force retaining member 70 to pivot counter-clockwise, slightly, untilpins 73 ride over and past engagement portions 72.

In order to permit the cocking of automatic tissue sampling apparatus20, without having to overcome the combined force of both of springs 55and 56, and as well to permit the inspection of the tissue sample oncethe sample has been taken (in a manner described hereinafter), theautomatic tissue sampling apparatus 20 has been provided with a tissuesample inspection feature and is configured so that yokes 46 and 47 arecocked and retained against springs 55 and 56, respectively, duringseparate, successive actuations of lever 28. Specifically, yoke 46 isconfigured to normally be freely, axially movable relative to shaft 40(aside from the biasing force of spring 55). However, catch member 74 ispivotably supported about pin 75 in a forward portion of yoke 46. Catchmember 74 is biased, by spring 76, for example, in a clockwise directionupwardly away from shaft 40. However, yoke 47 is provided withrearwardly projecting pin 78 which, when yoke 47 has been drawn backwardagainst central support 39, projects through a horizontally extendingaperture (not shown) in central support 39 to depress catch member 74downwardly toward shaft 40 so that the forwardmost edge of catch member74 is held against the bottom of recess 65, as illustrated in FIG. 7.When lever 28 has been actuated again, the forward edge of catch member74 abuts and is caught by the forward edge 7 of recess 65 and shaft 40,thereby pushing yoke 46 backward toward rear wall 26 and retainingmember 58.

Yoke 47 additionally has rearwardly projecting pin 140 (see FIGS. 2, 3and 4), which also is configured to pass through a horizontallyextending aperture (not shown) in and extend beyond central support 39,even when yoke 47 is positioned immediately adjacent central support 39.A bore 1 41 is provided in the forward face of yoke 46, which is alignedto receive pin 140. Spring 142 is arranged to snugly fit within bore141. The strength and stiffness of spring 142 is sufficient such thatwhen pin 140 projects into bore 1 41, under the impulse of spring 46,spring 142 will yield slightly and then resist further compression, sothat yoke 46 will be forced away from central support 39, as yoke 47 isdriven to and retained substantially adjacent central support 39.

The release of prior art yoke 46 is accomplished by pressing button 36,which pushes forward the upper end of the vertical portion of retainingmember 58, simultaneously causing engagement portions 60 of retainingmember 58 to pivot downwardly to remove the obstruction of pins 61 ofyoke 46. Propelled by the force of spring 55, yoke 46 moves forwardrapidly. Contact is first made between spring 142 in bore 141, and pin140. Immediately, due to the stiffness of spring 142, yoke 46 begins todecelerate, although it continues to approach central support 39. Asyoke 46 continues to approach central support 39, secondary button 83contacts rearward end 84 of retaining member 70. When pushed bysecondary button 83, retaining member 70 pivots against the bias ofspring 79 (as shown in FIGS. 5-11), causing engagement portions 72 ofretaining member 70 to remove the obstruction of pins 73 of yoke 47.Yoke 47 is thereby released, and is propelled by spring 56 toward thefront end of apparatus 20. Substantially simultaneously, the forwardface of yoke 46 encounters bumper 80. As yoke 47 recedes, the reactiveforce produced by the combination of pin 140 and spring 142 is lessened,and yoke 46 is brought to a smooth halt against bumper 80, with norebound, and significantly reduced noise and jarring. Accordingly, whenbutton 36 is pressed, yokes 46 and 47 are released consecutively inrapid succession.

It has been noted that the prior art apparatus of FIGS. 1-12 hasprovided the additional advantage of a slightly prolonged exposure ofthe tissue holding region, as compared to the apparatus disclosed inSer. No. 07/753,602, now U.S. Pat. No. 5,284,156. This slightlyprolonged exposure, together with the still further reduction in shockduring sampling, has permitted a greater volume of tissue to occupy thetissue holding region, before capture, resulting in greater accuracy oflocation and an improved tissue sample.

As previously mentioned, the automatic tissue sampling apparatus 20 ofFIGS. 1-12 was configured to be used with a conventional two-needlebiopsy needle system 22 (having two separate large handles), the generalconfiguration of which is well known from the prior art. Biopsy needlesystem 22 is composed of two parts, first needle 86 and second needle96. First needle 86 consists of substantially solid shaft 87 withintegrated handle 88. Angled point 89 is positioned at the end of shaft87, opposite from handle 88, to facilitate insertion of the needlesystem into the tissue to be sampled. Proximate to point 89, tissueholding region 90 is cut-out from shaft 87, as illustrated in FIG. 6.When biopsy needle system 22 is inserted into a tissue to be sampled,and tissue holding region 90 is exposed, a portion of the tissue movesinto tissue holding region 90, and is sheared off and retained there asthe desired sample.

Shaft 87 is freely inserting received by hollow shaft 97 of secondneedle 96, with integrated handle 98. An aperture (not shown) extendsthrough the length of handle 98. Handles 88 and 98 are typicallyadditionally configured to be asymmetrical, particularly with tabs 92,and 99 a and 99 b, which have portions projecting perpendicularly fromhandles 88 and 98, respectively. As the length of shaft 87 exceeds thecombined length of hollow shaft 97 and handle 98, point 89, atsubstantially all times during normal use, is exposed.

The operation of prior art biopsy needle system 22, to obtain andretrieve a tissue sample, is as follows. When point 89 is inserted intoa tissue, first needle 86 and second needle 96 must be in theconfiguration shown in FIG. 5, that is, with second needle 86 movedforwardly relative to first needle 86, so that hollow shaft 97 coverstissue holding region 90 of shaft 87, but point 89 remains forwardmostand exposed.

Once first needle 86 and second needle 96 have been inserted into thetissue, first needle 86 is moved forward, with respect to second needle96, further into that particular region of the tissue, from which asample is to be retrieved. During this step, second needle 96 is to bestabilized, with respect to the patient and the tissue, for accuracy andfor the comfort of the patient.

As point 89 of first needle 86 proceeds further into the tissue, tissueholding region 90 becomes exposed. Since the tissue is not a rigidmedium, a portion of the tissue “flows” to fill in, at least partially,tissue holding region 90. To retrieve and remove the sample, secondneedle 96 is then rapidly thrust forward, relative to first needle 86,which, in turn, is stabilized relative to the patient and the tissue—toeventually shear off and enclose the tissue that had previously flowedinto tissue holding region 90.

As illustrated in FIGS. 5 through 11, hollow shaft 97 is also providedwith point 100, which is also angled so that the extreme tip 101 ofpoint 100 is positioned, when first needle 86 and second needle 96 arealigned, on the side of the shaft 15 in which tissue holding region 90is formed. Proper alignment of first needle 86 and second needle 96 isobtained when the projecting portions of tabs 92, 99 a and 99 b arealigned.

Accordingly, as second needle 96 is moved forward relative to firstneedle 86, extreme tip 101 cuts the tissue to leave a portion of thetissue within tissue holding region 90. As second needle 96 continues tomove forward, the tissue sample and tissue holding region 90 arecovered. At this point, first needle 86 and second needle 96 haveresumed the relative positions indicated by FIG. 5 and must be withdrawnfrom the patient together in that position, in order to prevent thetissue sample from being dislodged or contaminated by other tissue.

To accomplish such operations with precision, speed and a minimum ofdiscomfort to the patient, using manual methods, is extremely difficult.Prior art automatic tissue sampling apparatus 20 has enabled theforegoing procedure to be accomplished swiftly, with a substantiallyreduced level of discomfort to the patient, and with a high degree ofrepeatability of result from one procedure to the next.

FIGS. 5 through 11 illustrate the successive steps in the operation ofthe prior art automatic tissue sampling apparatus 20. In FIG. 5,automatic tissue sampling apparatus 20 is shown in an uncockedconfiguration. Hollow shaft 97 of second needle 96 covers tissue holdingregion 90 of first needle 86. A first actuation of lever 28 causes crossmember 64 to abut the front face yoke 47, driving yoke 47 against theforce of spring 56, into position to be retained by retaining member 70.This procedure draws second needle 96 backward relative to first needle86, thus exposing tissue holding region 90. As previously described,once yoke 47 has been drawn back and retained by retaining member 70,pin 78 depresses catch member 74 against the bias of spring 76.Accordingly, when lever 28 is returned to its lowered position,returning shaft 40 to its fully forward position, catch member 74 isforced into recess 65.

In addition, during the first actuation of lever 28, as yoke 47approaches central support 39, pin 140 passes through central support 39and contacts spring 142 within bore 141. Spring 142 compresses slightlyand then resists further compression, causing yoke 46 to be forced awayfrom central support 39, as described earlier.

A subsequent actuation of lever 28, again draws back shaft 40. However,leading edge 67 of recess 65 pushes on catch member 74 to force yoke 46further backward toward retaining member 58. The upper end of retainingmember 58 simultaneously pushes button 36 backward relative to rearwardprojecting portion 33 of housing 24. Returning lever 28 to its initialposition again places automatic tissue sampling apparatus 20 into aconfiguration ready for insertion of biopsy needle system 22 into thetissue to be sampled, or resampled, if required.

Due to the power and speed with which the yokes 46 and 47 are propelledforward, respectively, by springs 55 and 56, once button 36 isdepressed, and in view of the hazardous nature of the biopsy needlesystem, it is highly desirable to provide automatic tissue samplingapparatus 20 with an automatically deployed safety mechanism to preventactuation of automatic tissue sampling apparatus 20. The prior artapparatus of FIGS. 1-12 has been provided with such a safety mechanism,in part illustrated in FIG. 12.

FIG. 12 shows shaft 40 and safety button 35. Shaft 40 has arranged, uponan upper surface thereof, cam surface 110. Button 36 is formed in threeparts, forward large diameter portion 120, central narrow portion 121,and rearward large diameter portion 122. Safety button 35 is configuredas a substantially cylindrical rod having, on an upper surface thereof,an arcuate depression 111 formed thereon and extending substantiallylongitudinally along the axis of safety button 35. Safety button 35 isdisposed parallel to the transverse axis of housing 24, for limitedreciprocal movement in an aperture in projection 33. Upon the lower halfof safety button 35, a recess is carved out having a depth substantiallyequal to the depth of cam surface 110 and having a width slightlygreater than the width of shaft 40. When shaft 40 is in its forwardmostposition within housing 24, as shown in FIG. 5, shaft 40 occupies theposition, relative to safety button 35, indicated by the solid linebutton 35 in FIG. 12. As illustrated, recesses 111 and 112 are slightlyoffset in the transverse direction. Recess 111, when positioned relativeto shaft 40 as shown in the solid line figure in FIG. 12, enables therearward large diameter portion 122 of button 36 to pass over safetybutton 35, enabling button 36 to move forwardly sufficiently to pivotretaining member 58 and release yoke 46.

When lever 28 is cocked, shaft 40 is automatically moved in thedirection of the arrow B in FIG. 12 and cam surface 110 forces safetybutton 35 to move in the direction of arrow C and thus occupy theposition, relative to the shaft 40, shown as 35′. When lever 28 isreturned to its lower position, shaft 40 moves forward again relative tohousing 24. While recess 112 is at that time positioned over the widestpart of cam surface 110, safety button 35 is held by friction in itssafety position, with recess 111 offset to one side of shaft 40.Accordingly, if button 36 is depressed, the rearward large diameterportion 122 of button 36 abuts and is blocked by safety button 35. Onlywhen safety button 35 is pushed in the direction opposite arrow C inFIG. 12, so that recess 111 again becomes aligned with shaft 40, canbutton 36 be fully depressed, to actuate apparatus 20.

Once prior art biopsy needle system 22 has been positioned in thepatient and into the particular tissue to be sampled, and safety button35 moved to release button 35, automatic tissue sampling can beeffectuated. FIG. 10 illustrates automatic tissue sampling apparatus 20in a configuration only a split second after button 36 has been fullydepressed. Retaining member 58 has been pivoted counter-clockwise, withengagement surfaces 60 no longer obstructing pins 61. Yoke 46 is movingrapidly toward central support 39 under the impetus of spring 55. Shaft87 of first needle 86 is being propelled forward relative to hollowshaft 97 of second needle 96. Tissue holding region 90 is being exposed.Pin 140 connects with spring 142 (not shown in FIGS. 5-11) and causesyoke 46 to slow down in its forward movement. Yoke 46 continues forward,and secondary button 83 reaches retaining member 70 and causes it torotate counterclockwise, as illustrated in FIG. 11. Engagement surfaces72 of retaining member 70 clear pins 73 and thus yoke 47 is propelledforward by spring 56. Second needle 96 is brought forward so that shaft97 covers tissue holding region 90 of first needle 86. Yoke 46 isbrought to rest against bumper 80.

The first and second needles 86 and 96 respectively, are held togetherto facilitate removal of biopsy needle system 22 from the tissue beingsampled. Once removed from the patient, it is often desirable to inspectthe tissue holding region 90, in order to determine whether a sample hasbeen successfully taken and, if so, to enable deposit of the sample ontoa microscope slide, or other appropriate receptacle. Inspection oftissue holding region 90 is easily accomplished in the presentinvention-by merely applying a single stroke to actuating lever 28 afterit has been fired, in order to draw back second needle 96, asillustrated in FIG. 6. If a suitable sample has not been retrieved,after inspection, a second actuation of lever 28 draws back first needle86, and places the automatic tissue sample apparatus again in a fullycocked configuration, ready for the reinsertion of biopsy needle system22 into the tissue to be sampled.

An additional advantage of the construction of the prior art apparatusof FIGS. 1-12, is that the provision of pin 140, spring 142, and bumpers80 and 130 prevent actual contact between yokes 46 and 47, and centralsupport 39 and forward wall 131, which tend to reduce the noiseotherwise associated with such apparatus. In addition, the decelerationproduced by these elements tends to reduce the “shock” which may be feltwhen apparatus 20 is actuated. Noise and shock are further reduced byfabricating bumpers 80 and 130 from resilient compressible plastic orrubber material, and by fabricating yokes 46 and 47 from nylon orsimilar materials. By reducing noise and shock, the patient'sdiscomfort, actual and/or perceived, during the sampling procedure, wasreduced.

FIGS. 13-15 illustrate an alternative prior art automatic tissuesampling apparatus. While the previously described embodiments compriseimprovements over the prior art, the embodiment of FIGS. 13-15 comprisedan even further improvement over the prior art. It has been observedthat manipulation of the previously described embodiments can, onoccasion, be complex, in that the physician or medical technician who isoperating the device, typically grasps an apparatus 20 at the front endof housing 24, while the end of needle 22 is being positioned into apatient. The grasping is typically done one-handed, as the operator istypically holding an ultrasonic sender-sensor in the other hand, whileobserving placement of the end of needle 22 on the display of theultrasonic device. Once the end of the needle has been positioned, thenthe operator must shift his grip on apparatus 20, in order to reachfiring button 36 to fire apparatus 20. The shifting of the grip is notonly inconvenient to the operator, it can cause shifting of thepositioning of the end of the needle 22, within the patient, bothcompromising the accuracy of the tissue sampling, and possibly causingadditional discomfort to the patient.

In yet other uses, the device is placed into a staging fixture, whichgrips the apparatus at various locations, and which often requiresmanipulation or adjustment toward the front of the apparatus.

Prior art apparatus 150 is operably configured to alleviate theaforementioned potential problems presented by the required shifting ofgrip by an operator. Apparatus 150 includes a front-accessible firingbutton 152, which enables apparatus 150 to be fired, one-handed, or fromwithin a staging fixture—without the operator having to shift grip aftercompleting placement of the end of needle 22, and without inadvertentmovement of the fixture. The location and recessing of the frontaccessible firing button 152 simultaneously avoids inadvertent actuationby the clamping elements of a staging fixture.

While in the illustrated embodiment, apparatus 150 has both rear firingpin 36 as well as front firing button 152, in yet another embodiment,rear firing pin 36 may be replaced with a shortened member which doesnot project outwardly from the rear of apparatus 150, such thatactuation of apparatus 150 may only be accomplished by front firingbutton 152.

The cocking, firing and safety mechanisms disclosed in FIGS. 1-12 arepresent in prior art apparatus 150, in substantially unmodified form,and so are only partially illustrated in phantom outline in FIGS. 13-15.Yokes 46 and 47 are representatively illustrated in their respectiveforward positions, although other constructions for contacting andpropelling the handles of the needle apparatus may be employed.Apparatus 150 includes a modified front plate 154, having apertures 156and 158, and rounded depression 160 into which firing button 152 may bedepressed.

Firing button 152 is formed from the externally exposed transverseportion of J-shaped firing member 162. Longitudinal portion 164 offiring member 162 extends along the interior of housing 166 of apparatus150, preferably in an appropriately configured channel or groove, suchas channel 168, to the side and out of the way of the movable yokes, inwhich are to be seated the handles of the needle apparatus.

Interconnection arm 170 is pivotably mounted on pin 172. Lower end 174of interconnection arm 170 is, in turn, pivotably connected to end 176of firing member 162. Lateral pin 178 emanates horizontally from upperend 180 of interconnection arm 170, and is operably positioned so as tobe pivotably received in lateral slot 182 in rear firing pin 184, whichis otherwise configured to be substantially identical to firing pin 36described with respect to the previous embodiment.

In the prior art embodiment of FIGS. 13-15, after apparatus 150 has beenloaded and armed, in the manner described with respect to the previousembodiment, firing button 152 was depressed, causing longitudinalportion 164 to move backwards, away from front plate 154. The lower end174 of interconnection arm 170 moves away from front plate 154.Interconnection arm 170 is forced to pivot, and lateral pin 178 pusheson the forward inside wall of slot 182, pushing/pulling firing pin 184forward. Face 186 of firing pin 184 pushes against the top of retainingmember 58, causing retaining member 58 to pivot about pin 188. Yoke 46is thereafter released, and apparatus 150 is actuated in the previouslydescribed manner, identical to the manner as if firing pin 184 (36 inthe previous embodiment) had been depressed.

There is no significant frictional resistance generated against themovement of any of firing member 162, interconnection arm 170, pin 172,or lateral pin 182, apart from that encountered directly resulting fromthe resistance of retaining member 58 to release the rear yoke.

It is believed that apparatus 150, which may be fired either with frontfiring button 152, or, if rear firing pin 184 is provided, rear firingpin 184, has provided an improved operation, particularly for thoseoperators who may grasp apparatus 150 either manually or in a fixture,along the front of housing 166, in that front firing button 152 enablesactuation of apparatus 150, without the need of the operator toreposition his/her grip, before firing. Firing button 152 was positionedwithin rounded depression 160, so as to be substantially flush with theface of front plate 154, so that, when apparatus 150 is armed, apositive inward pushing movement is required to fire apparatus 150, andthe likelihood of accidental firing, such as by contact with a flatsurface, from the fixture or otherwise, is substantially reduced.

FIGS. 16-34 illustrate a preferred embodiment of the present invention,automatic tissue sampling apparatus 20′, which is substantially similarin general operation to the prior art embodiment of FIGS. 1-12, in termsof the general cocking mechanism and cocking actions, and substantiallysimilar to the prior art embodiment of FIGS. 13-15, in that it isprovided with both a forward-firing and rear firing actuator andassociated mechanism. Accordingly, structural elements which are thesame or similar in structure and operation to analogous structuralelements which are shown and described with respect to the prior artembodiments of FIGS. 1-12 and 13-15, are given like references numerals,augmented by a prime (′) in the figures, and those portions of thedescriptions of FIGS. 1-12 and 13-15, which are directed to suchsimilarly referenced structures in the embodiment of FIGS. 16-34 shouldbe deemed applicable to the embodiment of FIGS. 16-34.

Automatic tissue sampling apparatus 20′, illustrated in FIG. 16,includes housing 24′ with cover 25′. Automatic tissue sampling apparatus20′ is cocked using lever 28′, which is provided with thumb rest portion30′. Lever 28′ is mounted for facilitated pivotal movement around pin32′. Spring catch 37′ holds cover 25′ in the closed position, but uponmoderate upward pressure to cover 25′, will deflect sufficiently torelease cover 25′. Central support 39′ is fixably mounted generallyalong the longitudinal center of housing 24′, and generally divides theinterior of housing 24′ into a forward region and a rearward region.Shaft 40′ is arranged for reciprocating axial movement substantiallyparallel to the longitudinal axis of housing 24′, and is mechanicallyconnected to lever 28′ by crank 42′, which is, in turn, pivotablyconnected to lever 28′ by pin 43′ and pivotably connected to shaft 40′by pin 44′. Accordingly, when lever 28′ is pivoted in the directionindicated by arrow A (FIG. 16), shaft 40′ moves axially backward withrespect to housing 24′. Yokes 46′ and 47′ are each configured to beretained within housing 24′ by projecting tabs, such as tab 49′ of yoke46′, which are received within longitudinally extending grooves, such asgroove 50′. Accordingly, yokes 46′ and 47′ are each configured to belongitudinally, slidably moved relative to support housing 24′.

In this preferred embodiment of the invention, shaft 40′ is configuredto pass through yokes 46′ and 47′, through apertures 23′ and 53′,respectively. Yokes 46′ and 47′ are each biased forwardly, with respectto housing 24′, by coil springs 55′ and 56′, respectively. When yoke 46′is drawn toward rear wall 26′ of housing 24′ during cocking (asdescribed hereinafter), it is engaged and retained adjacent rear wall26′ by retaining member 58′. Retaining member 58′ is normally biased topivot in a clockwise direction around axis 59′ so that engagementportions 60′ of retaining member 58′ are normally biased to moveupwardly relative to housing 24′. Engagement portions 60′, which arewedge-shaped, are driven downwardly by pins 61′, until pins 61′ pass therear edges of engagement portions 60′, as yoke 46′ approaches rear wall26′. Once pins 61′ have passed the rear edges of engagement portions60′, retaining member 58′ is permitted to then rotate clockwise and pins61′ abut the rear edges of engagement portions 60′, preventing yoke 46′from being driven forward under the bias of now-compressed spring 55′.

Spring 62′ is weaker than either of springs 55′ or 56′. At one end itabuts yoke 47′ and at the other end it abuts cross member 64′. Spring62′, being at all times in a slightly compressed configuration, tends topush cross member 64′ and yoke 47′ apart, thereby tending to maintainshaft 40′ in a forwardly drawn position with respect to, andsubstantially fully within, housing 24′. Shaft 40′ is provided with alongitudinally extending recess 65′ with sharply defined end surfaces66′ and 67′.

Yoke 47′ is illustrated, in FIG. 19, in its retained position againstcentral support 39′. To draw yoke 47′ against central support 39′,against the bias of spring 56′, when lever 28′ is actuated, cross member64′ abuts the front edge of yoke 47′ and forces yoke 47′ backward towardcentral support 39′. Yoke 47′ is restrained in that position byretaining member 70′, which is arranged for pivotal movement about axis71′. Retaining member 70′ includes engagement portions 72′, which engagepin 73′ in substantially the same manner as engagement portions 60′ ofretaining member 58′ engage pins 61′ of yoke 46′. Retaining member 70′is, like retaining member 58′, biased to pivot toward the clockwisedirection and engagement portions 72′ are wedge-shaped so that as yoke47′ approaches central support 39′, pins 73′ force retaining member 70′to pivot counter-clockwise, slightly, until pins 73′ ride over and pastengagement portions 72′.

In order to permit the cocking of automatic tissue sampling apparatus20′, without having to overcome the combined force of both of springs55′ and 56′, and to permit the inspection of the tissue sample once thesample has been taken (in a manner described hereinafter), the automatictissue sampling apparatus 20′ has been provided with a tissue sampleinspection feature and is configured so that yokes 46′ and 47′ arecocked and retained against springs 55′ and 56′, respectively, duringseparate, successive actuations of lever 28′. Specifically, yoke 46′ isconfigured to normally be freely, axially movable relative to shaft 40′(aside from the biasing force of spring 55′). However, catch member 74′is pivotably supported about pin 75′ in a forward portion of yoke 46′.Catch member 74′ is biased, by spring 76′ and pin 76A, for example, in acounterclockwise direction downwardly toward 40′. When yoke 46′ ispushed away from support 39′ (as described below), the vertical face74A′ of catch member 74′ moves away from pin 78′ (which is biased byspring 78A′ to move slightly, when yoke 46′ bumps into support 39′during the firing process), permitting catch member 74′ to pivot in thecounterclockwise direction. When lever 28′ has been actuated again, theforward edge of catch member 74′ abuts, and is caught by, the forwardedge 66′ of recess 65′ and shaft 40′, thereby pushing yoke 46′ backwardtoward rear wall 26′ and retaining member 58′.

Yoke 47′ additionally has rearwardly projecting pin 140′, which also isconfigured to pass through a horizontally extending aperture in (andextend beyond) central support 39′, even when yoke 47′ is positionedimmediately adjacent central support 39′. A bore 141′ is provided in theforward face of yoke 46′, which is aligned to receive pin 140′. Spring142′ is arranged to snugly fit within bore 141′. The strength andstiffness of spring 142′ is sufficient such that when pin 140′ projectsinto bore 141′, under the impulse of spring 46′, spring 142′ will yieldslightly and then resist further compression, so that yoke 46′ will beforced away from central support 39′, as yoke 47′ is driven to andretained substantially adjacent central support 39′.

The release of yoke 46′ is accomplished by pressing button 36′, whichpushes forward the upper end of the vertical portion of retaining member58′, simultaneously causing engagement portions 60′ of retaining member58′ to pivot downwardly to remove the obstruction of pins 61′ of yoke46′. Propelled by the force of spring 55′, yoke 46′ moves forwardrapidly. Contact is first made between spring 142′ in bore 141′, and pin140′. Immediately, due to the stiffness of spring 142′, yoke 46′ beginsto decelerate, although it continues to approach central support 39′. Asyoke 46′ continues to approach central support 39′, secondary button 83′contacts rearward end 84′ of retaining member 70′. When pushed bysecondary button 83′, retaining member 70′ pivots against the bias ofspring 79′ causing engagement portions 72′ of retaining member 70′ toremove the obstruction of pins 73′ of yoke 47′. Yoke 47′ is therebyreleased, and is propelled by spring 56′ toward the front end ofapparatus 20′. Substantially simultaneously, the forward face of yoke46′ encounters bumper 80′. As yoke 47′ recedes, the reactive forceproduced by the combination of pin 140′ and spring 142′ is lessened, andyoke 46′ is brought to a smooth halt against bumper 80′, with norebound, and significantly reduced noise and jarring. Accordingly, whenbutton 36′ is pressed, yokes 46′ and 47′ are released consecutively inrapid succession.

It has been noted that the apparatus of the present invention providesthe additional advantage of a slightly prolonged exposure of the tissueholding region, as compared to the apparatus disclosed in the prior artapparatus disclosed in Ser. No. 07/753,602, now U.S. Pat. No. 5,284,156.This slightly prolonged exposure, together with the still furtherreduction in shock during sampling, permits a greater volume of tissueto occupy the tissue holding region, before capture, resulting ingreater accuracy of location and an improved tissue sample.

The automatic tissue sampling apparatus 20′ of the present invention isconfigured to be used with a conventional two-needle biopsy needlesystem such as that disclosed in Terwilliger, U.S. Pat. No. 6,110,129(the complete disclosure of which is hereby expressly incorporatedherein by reference), and a version of which has been previouslymarketed and sold under the mark Pro-Mag™ I 2.2 and versions of whichare presently being marketed and sold under the marks Pro-Mag Ultra™ andPro-Mag Ultra ST™, by Inter-V Manan. Such a needle system is shown inperspective view in FIG. 35. Although this system has a somewhatdifferently configured handle structure, from the prior art needlesystem shown in FIGS. 2-11, the functional and dynamic relationshipsbetween the inner and outer needles and their respective handles, duringthe cocking and firing processes are the same. One may simply makereference to the movement steps described with respect to FIGS. 5-11, toreadily understand how the needle system for the embodiment of FIGS.16-34 operates. In particular, with the automatic tissue samplingapparatus in the configuration shown in FIG. 17, a needle system isinserted, and the cover closed. After two successive cocking motions ofhandle 28′, the apparatus is ready for positioning of the needle tip atthe site to be sampled, and can be fired to effect the samplingprocedure.

Due to the power and speed with which the yokes 46′ and 47′ arepropelled forward, respectively, by springs 55′ and 56′, once button 36′is depressed, and in view of the hazardous nature of the biopsy needlesystem, it is highly desirable to provide automatic tissue samplingapparatus 20′ with an automatically deployed safety mechanism to preventactuation of automatic tissue sampling apparatus 20′. The presentinvention is provided with such a safety mechanism, in part illustratedin FIGS. 18, 19, 26 and 34.

Like the embodiment of FIGS. 13-15, the embodiment of FIGS. 16-34 isprovided with a forward-firing mechanism, which is substantially, if notentirely, identical to that illustrated in and described with respect toFIGS. 13-15.

Apparatus 20′ includes a front-accessible firing button 152′, whichenables apparatus 20′ to be fired, one-handed, or from within a stagingfixture—without the operator having to shift grip after completingplacement of the end of the needle system, and without inadvertentmovement of the fixture. The location and recessing of the frontaccessible firing button 152′ simultaneously avoids inadvertentactuation by the clamping elements of a staging fixture.

Apparatus 20′ includes a modified front plate 154′, having apertures156′ and 158′, and rounded depression 160′ into which firing button 152′may be depressed.

Firing button 152′ is formed from the externally exposed transverseportion of J-shaped firing member 162′. Longitudinal portion 164′ offiring member 162′ extends along the interior of 24′ of apparatus 20′,preferably in an appropriately configured channel or groove, to the sideand out of the way of the movable yokes, in which are to be seated thehandles of the needle apparatus.

Interconnection arm 170′ is pivotably mounted on pin 172′. Lower end174′ of interconnection arm 170′ is, in turn, pivotably connected to end176′ of firing member 162′. Lateral pin 178′ emanates horizontally fromupper end 180′ of interconnection arm 170′, and is operably positionedso as to be pivotably received in lateral slot 182′ in rear firing pin36′, which is configured to be substantially identical to firing pin 184described with respect to the embodiment of FIGS. 13-15.

In this preferred embodiment, after apparatus 20′ has been loaded andarmed, in the manner described with respect to the previous embodiment,firing button 152′ is depressed, causing longitudinal portion 164′ tomove backwards, away from front plate 154′. The lower end 174′ ofinterconnection arm 170′ moves away from front plate 154′.Interconnection arm 170′ is forced to pivot, and lateral pin 178′ pusheson the forward inside wall of slot 182′, pushing/pulling firing pin 36′forward. Face 186′ of firing pin 36′ pushes against the top of retainingmember 58′, causing retaining member 58′ to pivot about pin 59′. Yoke46′ is thereafter released, and apparatus 20′ is actuated in thepreviously described manner, identical to the manner as if firing pin36′ had been depressed.

In a preferred embodiment of the invention, there is no significantfrictional resistance generated against the movement of any of firingmember 162′, interconnection arm 170′, pin 172′, or lateral pin 182′,apart from that encountered directly resulting from the resistance ofretaining member 58′ to release the rear yoke.

It is believed that apparatus 20′, which may be fired either with frontfiring button 152′, or, if rear firing pin 36′ is provided, with rearfiring pin 36′, provides an improved operation, particularly for thoseoperators who may grasp apparatus 20′ either manually or in a fixture,along the front of housing 24′, in that front firing button 152′ enablesactuation of apparatus 150′, without the need of the operator toreposition his/her grip, before firing. Firing button 152′, in apreferred embodiment of the invention, is positioned within roundeddepression 160′, so as to be substantially flush with the face of frontplate 154′, so that, when apparatus 20′ is armed, a positive inwardpushing movement is required to fire apparatus 20′, and the likelihoodof accidental firing, such as by contact with a flat surface, from thefixture or otherwise, is substantially reduced.

There are significant differences between the apparatus of FIGS. 1-12and that of FIGS. 16-34. For example, referring to FIG. 18, pin 76A isprompted by spring 76′ to push catch member 74′ downwardly, toward andinto recess 65′ during the cocking process. Similarly, catch member 74′is prompted out of recess 65′ during the cocking process by pin 78′which is prompted toward catch member 74′ by spring 78A′. Furthermore,sampling apparatus 20′ is configured to use double-needle biopsy needlessuch as those disclosed in Terwilliger, U.S. Pat. No. 6,110,129, whichhave integrated, sliding handles, which, while different in appearance,are configured to move, relative to one another in substantially thesame manner as the needle construction shown with respect to theembodiments of FIGS. 1-12 and 13-15. Accordingly, sampling apparatus 20′is provided with yokes 46′ and 47′ which are provided with a somewhatdifferent construction than yokes 46 and 47 of the embodiment of FIGS.1-12, or of FIGS. 13-15.

Amongst these significant differences, the improved safety lockconstruction of the embodiment of FIGS. 16-34 is shown in particular inFIGS. 18, 19, 26 and 34. FIG. 34 shows shaft 40′ and safety button 35.Shaft 40′ includes notch 110′. Firing button 36′ is formed in fourparts, forwardmost narrow portion 123′, with transverse notch 124′,forward large diameter portion 120′, central narrow portion 121′, andrearward large diameter portion 122′ (see FIG. 19). Safety button 35′ isconfigured as a substantially cylindrical rod having, on an uppersurface thereof, an arcuate depression 111′ formed thereon and extendingsubstantially longitudinally along the axis of safety button 35′. Safetybutton 35′ is disposed parallel to the transverse axis of housing 24′,for limited reciprocal movement in an aperture in projection 33′. Uponthe lower half of safety button 35′, a recess is carved out having adepth substantially equal to the depth of notch 110′ and having a widthslightly greater than the width of shaft 40′. When shaft 40′ is in itsforwardmost position within housing 24′, shaft 40′ occupies theposition, relative to safety button 35′, indicated by the solid linebutton 35′ in FIG. 34. As illustrated, recesses 111′ and 112′ areslightly offset in the transverse direction. Recess 111′, whenpositioned relative to shaft 40′ as shown in the solid line figure inFIG. 34, enables the rearward large diameter portion 122′ of button 36′to pass over safety button 35′, enabling button 36′ to move forwardlysufficiently to pivot retaining member 58′ and release yoke 46′.

In order to enable lever 28′ be cocked, safety button 35′ must be movedfrom a right hand position (relative to the operator when the apparatus20′ is being held by the operator at the rear of the device, and facingthe device), which is the solid line position shown in FIG. 34, to aleft hand position, which is the broken line position 35″ shown in FIG.34. When lever 28′ is returned to its lower position, shaft 40′ movesforward again relative to housing 24′. Accordingly, if button 36′ isdepressed, the rearward large diameter portion 122′ of button 36′ abutsand is blocked by safety button 35′. Only when safety button 35′ ispushed in the direction opposite arrow C in FIG. 34, so that recess 111′again becomes aligned with shaft 40′, can button 36′ be fully depressed,to actuate apparatus 20′. Because notch 110′ has a length which is onlyslightly greater than the diameter of that portion of button 35′ whichengages it, when button 35′ has been pushed to the right (opposite thedirection of arrow C), it is impossible to pull lever 28′ upwardly anysignificant distance would could result in misalignment of thecomponents in apparatus 20′ during the firing action, which could inturn result in misfiring or internal damage to the apparatus 20′.

As mentioned, when the sampling apparatus 20′ is at its “at-rest”,uncocked configuration, safety button 35′ may be substantially freelyslid from one side to the other. In order to provide some slightresistance to lateral movement, button 35′ is provided with twodepressions 160′, 162′. Spring 176′ mounted in a bore in housing 24′prompts ball 164′ toward button 35′. Depressions 160′, 162′ representthe “on” and “off” positions of the safety button 35′. The force exertedby spring 176′ and ball 174′, when ball 174′ is seated in one ofdepressions 160′ or 162′ is sufficient to prevent button 35′ from simplysliding free (if, for example, apparatus 20′ is tilted from one side tothe other) to prevent inadvertent setting or releasing of the safetylock mechanism, but not so forceful as to make shifting of button 35′difficult. Simply put, when the safety button is in the first position,shown in solid lines in FIG. 34, one can operate the rear firing memberbut cannot operate the cocking lever. Alternatively, when the safetybutton is in the second position, shown in broken lines in FIG. 34, onecan operate the cocking lever, but cannot depress the rear firingmember.

While the safety lock of the present invention has been disclosed withrespect to the apparatus of FIGS. 16-34, which uses a particular needlesystem, being that shown in Terwilliger, U.S. Pat. No. 6,110,129, it isto be understood that the safety lock structures may be adapted to otherautomatic tissue sampling apparatus, which employ different needlesystems, such as the automatic tissue sampling apparatus disclosed inSchramm et al., U.S. Pat. No. 5,284,156; Schramm et al., U.S. Pat. No.5,476,101; and Schramm et al., U.S. Pat. No. 5,507,298, wherein needlesystems having larger, discrete handles are employed.

The foregoing description and drawings merely explain and illustrate theinvention and the invention is not limited thereto except insofar as theappended claims are so limited, as those skilled in the art who have thedisclosure before them will be able to make modifications and variationstherein without departing from the scope of the invention.

1. An automatic tissue sampling apparatus, for use with a biopsy needlesystem of the kind including a first needle having a shaft member andtwo ends, a first handle disposed at one end of the shaft member, acutting point disposed at the other end of the shaft member, and atissue holding region positioned between the cutting point and the firsthandle, and a second needle having a hollow shaft, a cutting pointdisposed at one end of the hollow shaft, a second handle with apassageway arranged therethrough for reciprocation of the first needle,the automatic tissue sampling apparatus comprising: a housing; handleholders, operably disposed in the housing, for receiving and holding thefirst and second handles of the first and second needles, toward movingsame; a propulsion mechanism, operably disposed in the housing, formoving the handle holders within the housing, so as to move the needlehandles to expose and subsequently cover, the tissue holding region,when the biopsy needle system has been positioned at a desired locationwithin a tissue to be sampled, the propulsion mechanism being operablybiased so as to tend to move the handle holders so as to expose andsubsequently cover the tissue holding region, unless the handle holdersare restrained; a cocking mechanism, for placing the handle holders,and, in turn, the first and second needles of the biopsy needle systeminto suitable respective positions within the housing for subsequentmovement by the propulsion mechanism; a retaining mechanism, for holdingthe handle holders, and, in turn, the first and second needles of thebiopsy needle system in the suitable respective positions within thehousing, prior to actuation of the apparatus; a release mechanism, foractuating the retaining mechanism, so as to release the handle holdersand enable the propulsion mechanism to move the first and secondneedles, so as to expose, and subsequently cover the tissue holdingregion, a firing mechanism, operably connected to the release mechanism,for causing the actuation of the propulsion mechanism; and a safety lockmechanism, operably interconnected between the firing mechanism and thecocking mechanism, for precluding undesired actuation of the firingmechanism until the handle holders are fully cocked, and for precludingundesired movement of the cocking mechanism, during actuation of thefiring mechanism.
 2. The automatic tissue sampling apparatus accordingto claim 1, wherein the cocking mechanism comprises: a cocking shaft,mounted in the housing for longitudinal reciprocating movement therein,and operably interconnected with the handle holders; and a cocking leverpivotably mounted on a rear wall portion of the housing, proximate thefiring mechanism, and connected to the cocking shaft so that upon upwardpivoting of the cocking lever, the cocking shaft is drawn rearwardlyrelative to the housing.
 3. The automatic tissue sampling apparatusaccording to claim 2, wherein the safety lock mechanism comprises: asafety button, mounted in the rear portion of the housing, forreciprocating movement in a direction transverse to the cocking shaftbetween first and second positions, the safety button having engagementstructures disposed thereon, configured for selective engagement withthe cocking shaft, when the safety button is in its first position, andwith the rear firing member, when the safety button is in its secondposition, so that when the safety button is in its first position, thecocking shaft and, in turn, the cocking lever, are precluded frommovement, and when the safety button is in its second position, thefiring button is precluded from movement.
 4. The automatic tissuesampling apparatus according to claim 3, wherein the safety button has afirst notch, with an engagement shoulder therein, operably configured toenable the cocking shaft to move relative to the safety button when thesafety button is in its second position, and to engage with a shoulderdisposed on the cocking shaft to prevent movement of the cocking shaftrelative to the safety button, when the safety button is in its firstposition.
 5. The automatic tissue sampling apparatus according to claim3, wherein the safety button has a second notch, operably configured toenable the rear firing button to move, when the safety button is in itsfirst position, and to engage with a shoulder disposed on the rearfiring button, to preclude movement thereof, when the safety button isin its second position.
 6. The automatic tissue sampling apparatusaccording to claim 1, wherein the firing mechanism comprises: a rearfiring member operably positioned on a rearward portion of the housing.7. The automatic tissue sampling apparatus according to claim 1, furthercomprising: a front firing member operably positioned on a forwardportion of the housing, the front firing member being operablyinterconnected with the rear firing member.